Inner Air Filter L2501

Tornado

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I learned recently that the L2501 does not have the inner air filter that many of the other Kubota models have. I think this also goes for the L3301 and 3901 as well. I read that some folks had ordered it and installed it on their L, so I decided to do the same. It should be on my porch when I get home today from work, along with the additional right hand handle. Im just curious if anyone knows why Kubota makes a decision like this regarding the air filter. It was $15.70 for me to buy it. Is it just one of those small things they nix as a cost saving measure? As a new owner, It just seems to me that thins you wouldn't want to gimp on are anything that deals with the good function of the engine notably air and fuel delivery. Perhaps the thinking is that the L series isn't considered to be a model that will "spend hours in the field everyday" so it doesn't need the added protection? Just curious what some of the more knowledgeable folks here think about it. I was a little perplexed when I first read about it.
 

SidecarFlip

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Probably for the same reason they discontinued the really nice bucket level indicator and went to the flat metal welded on the bucket top and / or the rod and welded ear. The old style articulated weldment and tube was much better but more costly. Just bought a new one to replace a damaged one. 25 bucks.

All about cost savings.
 

Roadworthy

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I learned about the added air filter here on OTT so I inquired. The local mechanic feels it is not required in my case. If I was using the tractor all day every day in very dusty conditions he said I should use the filter. I do live in a very dusty environment but don't think I average more than fifty hours use a year. I didn't get the filter but I'm still considering it.
 

Tornado

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I learned about the added air filter here on OTT so I inquired. The local mechanic feels it is not required in my case. If I was using the tractor all day every day in very dusty conditions he said I should use the filter. I do live in a very dusty environment but don't think I average more than fifty hours use a year. I didn't get the filter but I'm still considering it.
I 100% understand your thought process here. I will be about like you, I suspect 50-100 hours per year I will put on my tractor. My thing is this though - does having the inner filter HURT the tractor in any way? I cant see how it would. Does having the inner filter HELP the tractor in any way.... While it is true my low usage may not see much impact from the additional protection, I ask myself why not? it's $15. It will gurantee just a bit more that no dust particles make it into the engine. Just the peace of mind knowing the extra filter is there is worth the $15 to me.

This is likely why the dont include it htough i suspect. Its not really an "agriculture" level tractor, and more of a utility type tractor that is designed for people to do little projects with here and there, not high hour work. I guess they assume it is a safe cut in this type tractor for that reason. I will be using mine, as I have already, for land clearing and pushing limbs and trees into piles. I run into dust often, and often have fires burning so driving through smoke and such. Im glad I came across the knowledge of the inner air filter.
 

ccoon520

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I 100% understand your thought process here. I will be about like you, I suspect 50-100 hours per year I will put on my tractor. My thing is this though - does having the inner filter HURT the tractor in any way? I cant see how it would. Does having the inner filter HELP the tractor in any way.... While it is true my low usage may not see much impact from the additional protection, I ask myself why not? it's $15. It will gurantee just a bit more that no dust particles make it into the engine. Just the peace of mind knowing the extra filter is there is worth the $15 to me.

This is likely why the dont include it htough i suspect. Its not really an "agriculture" level tractor, and more of a utility type tractor that is designed for people to do little projects with here and there, not high hour work. I guess they assume it is a safe cut in this type tractor for that reason. I will be using mine, as I have already, for land clearing and pushing limbs and trees into piles. I run into dust often, and often have fires burning so driving through smoke and such. Im glad I came across the knowledge of the inner air filter.
It may (emphasis on may) reduce the power produced by the engine. Think about the effect of breathing through a respirator vs breathing through a comforter. If the weave of the filter tightens up enough with the added filter the air flow could be reduced resulting in less oxygen to mix with the fuel resulting in lower power. I imagine it would at most reduce it a couple horsepower like if you lived in the Rockies vs the Plains.
 

Tornado

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It may (emphasis on may) reduce the power produced by the engine. Think about the effect of breathing through a respirator vs breathing through a comforter. If the weave of the filter tightens up enough with the added filter the air flow could be reduced resulting in less oxygen to mix with the fuel resulting in lower power. I imagine it would at most reduce it a couple horsepower like if you lived in the Rockies vs the Plains.
I had already thought of this, but I couldnt fathom that this internal filter could have that type of impact. I do plan to keep this in the back of my mind however after I install it to see if I notice anything. I just cant imagine an air filter that is used in other kubota models as standard issue choking the engine in the L. I have no mechanical knowledge to make that statement, just thinking on it and applying my basic logic.
 

Gillie Dog

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I had already thought of this, but I couldnt fathom that this internal filter could have that type of impact.
It is most likely an extra cost they do not see as necessary on this model for some reason.

I would not believe Kubota would offer it for this model if it had any determental effect on performance.

To me it is just an inexpensive insurance policy to show if the outer filter has failed. How long will it last without outer filter failure? Years, forever? Unknown.

The outer filter is cleaned and inner inspected about every 10 hours in "dust season". Probably over kill on cleaning but this last time it probably needed it. We will see.

GD
 
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007kubotaguy

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I take care of about 35 Kubota L2501 and L3200. TheL2501 did not come with inner air filters. If I put 10 hours or 500 hours a year on these tractors I would install the inner filter. That inner filter could save you lots of money. If something happened to the outer filter that is your only chance. With a $15 inner filter you have a second chance. $3,000 minimum to repair a dusted engine. The math doesn't work out. A good portion of the engine overhauls I do on tractors are related to air filter issues. On the older L series tractors I almost always update them to a dual filter system with the radial seal. The wing nut System causes problems as well.
Good luck Lance
 
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Fordtech86

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I added the inner filter to my L after I got mine. This time of year is extremely dusty here when mowing. I knock the dirt out of the outer filter every time I clean the radiator and screen. Inner filter still looks new. Cheap insurance like everyone else says. I change oil and filter, outer air filter and fuel filter every spring. I’m sure it’s overkill for my usage (around 100 hrs a year). No performance issues noticed either after installing inner filter.
 

Henro

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Is this inner filter a mesh filter like on my B2910?

If so, it would keep pieces of the outer filter out of the engine, but not dust.

OR is the inner filter actually a second air filter similar to the primary filter?

Just showing my ignorance I suppose. :eek:
 

North Idaho Wolfman

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Is this inner filter a mesh filter like on my B2910?

If so, it would keep pieces of the outer filter out of the engine, but not dust.

OR is the inner filter actually a second air filter similar to the primary filter?

Just showing my ignorance I suppose. :eek:
The inner filter they are talking about, is a very fine filter, stops just about anything the first didn't stop. ;)
 

Tornado

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So I got the filter Monday and installed it. To elaborate on some of the questions I saw here, the inner filter is, as Wolfman said above, a very fine filter. The walls of the filter arent super thick, but the material is very dense, almost like that of those thick paper work towels you can buy in the box, if you know what I mean. You can not see through this stuff. It is clearly designed to catch the smallest of particles that might would escape or otherwise find their way through the outer filter. My only concern after seeing it, and then putting the two filters together was "My god, thats a lot of material for air to pull through, I may starve it for air!" but after install and cranking the tractor, the intake port on the air box seemed to pull just as hard. I did just a basic 'place my hand over the port and measure the suction' test - very scientific, but I was curious.

One post in this thread mentioned that when they change their outer filter the inner filter always looks new. Ive read this elsewhere before as well - that that inner filter will collect very little over time, as the outter filter does seemingly most all the work. This means that when you do change your outer filter, you dont have to worry about exposing the central air intake to a dirty air box. There is a guy here where I live who runs one of the largest Stihl and grasshopper mower dealerships in the south east - He is well respected in the area and knows his stuff, He told me something one day that stuck with me when I was looking at lawn mowers. Regarding the air filter he said to just blow it off with a blower occasionally or something but don't actually remove it to 'tap it out' or 'shake it out'. He services a LOT of mowers, and he was making the point that constantly pulling dirty filters off to clean them can actually do more harm that good as you inevitably get dirt into the engine by removing the filter over and over and exposing the intake. He argued you are better off to just leave the filter on, only taking it off to replace it or to do one good deep clean on it. Having an inner air filter that you may hardly ever have to remove in this case helps prevent this issue. You can pull that outer filter off as much as you want, and ensire that the actual air intake sitting inside the inner filter is never exposed to a dirty air box. Thats worth $15 to me, Id recommend all owners of an L series to get it honestly, I just see no good argument against it.
 

Roadworthy

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I think the pros outweigh the cons. I'm picking up an inner air filter for my L2501 today. At less than $20 it's cheap insurance. If the outer filter does its job properly I should only need one inner filter for the life of the tractor - which should certainly far exceed my life expectancy.
 

rentthis

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When you remove the outer filter, it's good to have the inner filter in place. If the inner filter has anything on it, it had to have gotten past the outer filter telling you that you need to address the outer filter. If the inner filter stays clean, there is no reason to replace it.